Conventionally, in a vehicle having an in-wheel motor wherein the motor for generating driving force is provided in the wheel, a part such as a breather device maintaining a pressure within an enclosure of the motor at a constant level or a connector connected to a sensor detecting a temperature or the number of revolutions of the motor is provided on the outer peripheral section of the enclosure. For example, as a part provided at the enclosure of the in-wheel motor, a device detecting a fault of a magnetic detection sensor is disclosed in the following publication.
Japanese Patent Laying-Open No. 2000-224884 discloses a compact and lightweight detecting device capable of detecting a fault. This detecting device magnetically detects the rotation angle of the motor. The detecting device includes three or more magnetic detection sensors that are arranged at prescribed electrical angles and detect intensity of the magnetic field in a binary manner, an inverting device that inverts the output of at least one of the magnetic detection sensors, and an output device that outputs a sensor error when the outputs of all the magnetic detection sensors are equal.
According to the detecting device disclosed in the above-described publication, the output of one of the magnetic detection sensors is inverted to prevent the outputs of all the magnetic detection sensors from becoming identical. Thus, it can be determined, when detecting equal outputs from the magnetic detection sensors, that there is a fault of the detecting device, break of a cable of the detecting device, disconnection of a connector, or the like.
However, in the in-wheel motor, if a high power output is demanded for the motor or a so-called dynamic mass damper mechanism supporting the motor by a resilient member is provided to improve riding comfort of the vehicle, the structure of the in-wheel motor would increase in size. In such a case, the axial length of the motor may become greater than a width of the wheel, causing the enclosure of the motor to protrude from the wheel toward the inner side of the vehicle. If the above-described breather device, the connector provided for the sensor, or the detecting device disclosed in the above-described publication is provided at the region of the enclosure of the motor protruding from the wheel, flying stones kicked up by the wheel may bounce off the inner surface of the wheel house, and hit the above-described part to cause damage thereto.